Can you reduce your risk of Alzheimer's?

It's the second-most feared disease after cancer, an estimated 5.4 million Americans are living with it, and there's no cure: We're talking about Alzheimer's disease, a type of dementia that causes a steady decline in memory, thinking and behavior.

Scientists know Alzheimer's damages and kills brain cells; they also know that age, family history and genetics can increase your chances of developing the disease. But what they can't yet say for sure is exactly how to prevent it. The number of people with Alzheimer's is expected to skyrocket in the coming years. As researchers work to find effective prevention strategies, emerging science suggests there may be steps we can take to help reduce our risk. Here are three:

Control your blood sugar

A study recently published in the journal Neurology showed that people with diabetes are twice as likely to develop Alzheimer's as people with normal glucose levels. That's because high blood sugar and insulin resistance may lead to complications that could harm brain cells directly or damage the blood vessels that bring oxygen and nutrients to the brain.

Exercise

At the Alzheimer's Association International Conference this year, researchers reported on roughly how many cases of Alzheimer's may be attributable to certain behaviors or conditions; in the USA, physical inactivity topped the list. Regular exercise keeps your cardiovascular system healthy, which is good for your heart and your head; some studies suggest working out may directly benefit brain cells by increasing blood and oxygen flow.

Have your cholesterol checked

Scientists in Japan discovered that people who have high cholesterol levels were more likely to have markers for Alzheimer's in the brain called plaques compared with people who have normal or lower cholesterol. Another reason to watch your cholesterol: Conditions that damage the heart or blood vessels, including high cholesterol, high blood pressure and heart disease, appear to increase Alzheimer's risk.

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